California Gov. Gavin Newsom should “stop undermining the US on the world stage” and fix his own “broken” state, the White House told The Post in an exclusive statement Tuesday. The fiery comment came after Newsom  took a stab at the president  at the World Economic Forum in Davos , Switzerland, comparing him to a “T-Rex.” “Gavin Newsom should stop undermining the United States on the world stage and start fixing his own broken state back home,” White House Deputy Press Secretary Kush Desai